On Mon, Aug 21, 2023 at 03:12:18PM +0200, Petr Pavlu wrote:
> Use a notifier to implement mlx4_dispatch_event() in preparation to
> switch mlx4_en and mlx4_ib to be an auxiliary device.
>
> A problem is that if the mlx4_interface.event callback was replaced with
> something as mlx4_adrv.event then the implementation of
> mlx4_dispatch_event() would need to acquire a lock on a given device
> before executing this callback. That is necessary because otherwise
> there is no guarantee that the associated driver cannot get unbound when
> the callback is running. However, taking this lock is not possible
> because mlx4_dispatch_event() can be invoked from the hardirq context.
> Using an atomic notifier allows the driver to accurately record when it
> wants to receive these events and solves this problem.
>
> A handler registration is done by both mlx4_en and mlx4_ib at the end of
> their mlx4_interface.add callback. This matches the current situation
> when mlx4_add_device() would enable events for a given device
> immediately after this callback, by adding the device on the
> mlx4_priv.list.
>
> Signed-off-by: Petr Pavlu <[email protected]>
> Tested-by: Leon Romanovsky <[email protected]>
> Acked-by: Tariq Toukan <[email protected]>
> ---
> drivers/infiniband/hw/mlx4/main.c | 40 +++++++++++++-------
> drivers/infiniband/hw/mlx4/mlx4_ib.h | 2 +
> drivers/net/ethernet/mellanox/mlx4/en_main.c | 26 +++++++++----
> drivers/net/ethernet/mellanox/mlx4/intf.c | 24 ++++++++----
> drivers/net/ethernet/mellanox/mlx4/main.c | 2 +
> drivers/net/ethernet/mellanox/mlx4/mlx4.h | 2 +
> drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 2 +
> include/linux/mlx4/driver.h | 8 +++-
> 8 files changed, 75 insertions(+), 31 deletions(-)
>
Thanks,
Reviewed-by: Leon Romanovsky <[email protected]>